The fastest bike for Stage 4: California Dreamin'
- 21.2 km with the 2.1 km lead-in
- 106 m of climbing
- 1 lap
- 5.3 m/km climb ratio
- 1 named climb
- Surface96.3% tarmac2.8% dirt0.9% cobbles and wood
- Zwift disables TT frames for scratch races, so they are excluded from the ranking below. Everything listed is a bike you can actually start on.
- Zwift publishes this race as 19.1 km / 153 m; the figures above are this site's own totals from the route's lead-in and lap data, which is what the physics runs on.
Fastest eligible setup · Standard (Road) · verified data only · Halo bikes hidden
with Cadex 4-Spoke/Disc wheels
36:38
34.7 km/h averageestimated for 1 lap with the lead-in
- Data
- Frame and wheels bot-tested
- Upgrades
- Ranked at upgrade stage 5, assumed for bikes you don't own
- Rough surfaces
- Rough surfaces cost this setup about 11 seconds here
If Halo bikes are allowed
Specialized PROJECT 74 (Standard (Road))
A Halo bike · unlocking it takes three fully upgraded frames of one brand plus ~20 million Drops.
36:36
1.6 s faster
This is a scratch race, but the ranking below is computed for a lone rider with no draft at all. Race draft mode adds the draft a typical mid-pack racer measurably gets, calibrated on thirteen real race fields.
What bike should I ride for ZRacing 2026 – October: Tour of Watopia Stage 4?
Zwift disables TT frames for scratch races. ZwiftBikes predicts the Specialized S-Works Tarmac SL9 with Cadex 4-Spoke/Disc is the best bike and wheels for California Dreamin' in Watopia: the fastest road setup for a 75 kg rider at 225 W, finishing in 36:38 (~34.7 km/h). The Cervelo S5 with Cadex 4-Spoke/Disc is 0.24 s behind. With Halo bikes included, the Specialized PROJECT 74 is 1.6 s quicker.
75 kg / 175 cm / 225 W / solo; 1 lap, including any lead-in once. Standard (Road); verified only; unowned Halo bikes excluded.
Every setup, ranked
Gap to the fastest. Open a row for its wheels, upgrades and the numbers behind it.
| # | Frame and wheels | Time | Gap | Gap axis | Aero / climb | Style | Details |
|---|---|---|---|---|---|---|---|
| 1 | Cadex 4-Spoke/Disc | 36:38 | fastest | 95 / 83 | all-round | ||
| 2 | Cadex 4-Spoke/Disc | 36:38 | +0.24 s | 96 / 72 | aero | ||
| 3 | Same frame in another paint: Canyon Aeroad CFR Alpecin Premier-Tech Cadex 4-Spoke/Disc | 36:38 | +0.26 s | 95 / 74 | aero | ||
| 4 | Cadex 4-Spoke/Disc | 36:38 | +0.47 s | 94 / 82 | climbing | ||
| 5 | Cadex 4-Spoke/Disc | 36:39 | +0.75 s | 95 / 75 | aero | ||
| 6 | Cadex 4-Spoke/Disc | 36:39 | +0.82 s | 93 / 83 | all-round | ||
| 7 | Cadex 4-Spoke/Disc | 36:39 | +0.90 s | 95 / 75 | all-round | ||
| 8 | Cadex 4-Spoke/Disc | 36:39 | +1.15 s | 95 / 70 | aero | ||
| 9 | Cadex 4-Spoke/Disc | 36:39 | +1.26 s | 94 / 78 | aero |
Something here look wrong? Report it – corrections with a source get folded back into the data.
Why this bike wins here
California Dreamin' is flat, with 5.3 m of climbing per kilometre, the kind of course where aerodynamics usually counts for far more than low weight. The Specialized S-Works Tarmac SL9 is an all-round frame. Disc or regular wheels is a close call: the Cadex 4-Spoke/Disc is 3.6 s faster than the SwissSide HADRON Ultimate 650, but 0.37 kg heavier.
What the terrain rewards, from its climbing alone: aerodynamics against low weight
Aerodynamics 91%Weight on climbs 9%
- Drag area against the stock bike
- −0.0360 m²
- Mass against the stock bike
- −1.59 kg
- Rolling resistance change
- −0.0003
- Time lost to rough surfaces
- 11 s
- Physics model
- Dynamic, measured geometry
The course
1 lap; kilometre positions include the lead-in, ridden once.
- Fastest bike for Zwift KOM
Climb · km 9.0 to 9.9
0.9 km · 5.0% 45 m
Mapped surfaces; the shares describe one lap.
| Surface | Share | Distance | Extra watts |
|---|---|---|---|
| Tarmac | 96.3% | 18.4 km | - |
| Dirt | 2.8% | 0.5 km | - |
| Cobbles | 0.8% | 0.1 km | - |
| Wood | 0.1% | 0.0 km | - |
Extra watts are what the fastest setup needs to hold its pace on each surface rather than on tarmac, averaged over the ride - they appear once a ranked setup and mapped surface positions are there to simulate .
Specialized S-Works Tarmac SL9 / Cadex 4-Spoke/Disc · 225 W · Solo · one lap plus the lead-in; the finish estimate covers 1 lap. The line is this setup's simulated pace at every grade and surface change, over a faint elevation backdrop; the strip beneath marks the surface behind each dip.
Dynamic physics model active
Every time below is simulated for your weight, height and power over this route’s real, measured elevation data.
Racing a different number of laps, or riding this route outside the event? Fastest bike for California Dreamin'. It ranks every bike in the game, TT frames included – this race's rule is the race's, not the route's.
How this race tends to play out
California Dreamin' is the Tour's short race: 19.1 km as published, 21.2 km counting the lead-in, and almost all of it flat, with 106 m of climbing in total. The one real effort is the Zwift KOM about 7 km in, 0.9 km at 5%, and the rest is gentle rolling. The road is 96% tarmac, with a few short patches of dirt, wood and cobbles that add up to under 4%, so nothing on the surface changes the answer. With one short climb in a short, fast race this is an aero stage: expect the bunch to arrive at the KOM together and be shaped by the pace over the top, not by the climb itself.
Official event info – signup, full rules and results live with Zwift; we rank the bikes.
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